Ball-grinding machine



1,629,864 may 1927' w. a. GARDNER BALL GRINDING MACHI NE Filed Nov 26, 1923 a Sheds-Sheet 1 y 1927' w. a. GARDINER BALL'GRINDING MACHINE '11 NOV. 26. 1923 3 Sheets-Sheet 2 W. B. GARDINER BALL GRINDING MACHINE May 24 1927.

Filed Nov.

Patented May 24, 1927.

,,.WAL TER B. GAnmnnR, or HARTFORD, coNnEorIoU'r.

BALL-GRIN DIN G MACHINE.

Application filed November 2c, 1923. Serial No. 676,955.

- Fig. l-isa plan view of a ball grinding machine illustrating my invention.

' Fig. 2 is an end view of the same.-

Fig. 3 is av sectional view on the line"33 B of Fig. 1. Fig. v is asectiona-l view on the line 4-4 of Fig. 2. j i

- 'lhisinvention relates to improvement in ball-grinding machines, and particularly to 1 machines 'whichnre employed in the first step 'of preparing' balls for finishing. Grindmg machines ofthis character include an abrasive-disk, a, drive-ring and a raceway in whi'ch the balls are placed and rotated, so as tobeacted upon-by the abrasive-disk. In 4 such'machines a fixed pressure has been applied to the drive-ring to hold the balls against the'race-ring: This pressure must be suflicient to hold the balls and overcome the greatest pressure exerted against the balls by the abrasive-disk in the process of grinding. As this latterpressure is var1- able, subject to the control of the operator, the wear on the race-ring may be unnecessarily increased, for at any time when the pressure of the abrasive disk is less thanthe maximum, the fixed pressure on the balls between the drive-ring and the raceway becomes more than is necessary to hold and rotate the balls. The obj ect'oi my invention is to provide annutomatic device winch will force the abrasive disk against the balls with ra constant ressure to itsextreme cutting capacity with independent means to regulate the pressure to hold the balls between the drive-ring and raceway, thereby obtaining the maximum grinding action with the minimum wear on the parts,'-and the invention consists in the'constr uction.as hereinafter described and particularly recited inthe claims. In carrying out my invention, l-employ en'abrasive-disk 10 secured to-a metal-head ll-carried by a shaft 12 driven by-apulley 13 and journalled in an externallyt-hreuded sleeve 14,- thissleeve beingfsupported for longitudinal movement in bearings 15 and 16, and on this sleeve, between the bearings, is an adjusting-nut 17. A V-shaped raceway 22 is formed by a disk 18 secured to a/fixed stem 19, eccentric to the shaft 12, .and an outer portion 20, which is secured to the frame 21 of the machine Concentric with the raceway, is a bulldriving-ring 23 fixed to a head 24 .at the inner end of a tubular shaft 25, which suron the balls which constitute the rounds the stem 19 and which carries aar Wheel 26 meshing with adri-ve-pinionQ on a shaft 28-driven'by apulley 29. The tubular shaft 25 is concentrically journalled in an externally-screw-threaded sleeve 30 like the sleeve 14, and supported in bearings3l -and 32 and carrying a nut 33 between the bearings, by which the sleeve may be adusted longitudinally Pivoted to the frame 18 a yoke 34, the arms 35 of which straddle the bearing 16, so as to bear against the outer face of the nut 17. Thisyoke is pivoted at 36 and its end 37 is connected with one member 38 of a telescopic connecting-rod. The other member 39 of the connecting-rod passes through an adjustable collar 40, carried by a bracket 41 secured to the frame, the end of the member 39 being telescopicallyconnected with the end of the member- 38. Theorember 39 1S pivotally connected with the arm 42 of a yoke 43, like the yoke 34.'and having arms 44 which straddle the bearing 31 and have a bearing against the nut 33. Fixed to the member 38 is a spring-seat 45, and adjust-ably mounted on the member 39 is a corresponding seat 46, this being adjustably held in place by a nut 47 and between the two seats is a spring 48. On the rod 39, between the collar 40 and the arm 42 of the yoke, is a'spring 49., this spring being relatively light,-as compared to the spring 48.

The spring 48 applies constant pressure to the members 10 and 23 etc ual magnitude, or slightly greater magnitude on the member 23, and in the opposite direction, and

the spring 49 adds a small differential of pressure to the member 23, thus causing the pressure of the driving-ring to-be constantly greater than that of the grinding-member 10 work, thus assuring that said balls will remain pressed into the raceway.

Balls are fed to and removed from the machine in any proved manner.

In adjusting tie machine, the tubular bearing 25 is adjusted so as to bring the drive-ring and abrasive-disk to a proper relative position, so that. when balls are fed between them, they will be properly acted upon. When so adjusted, pressure is applied to sleeves l4 and 30 by the spring 48, which tends to separate the members 38 and 39 of the connecting-rod, between the yokes 34 and 43, so as to force the two sleeves toward each other, and hence the abrasivewheel and drive-ring. Thus, means are provided for applyinggrinding pressure to the balls, without decreasing their frictional contact with their raceway. In order that the balls should be rotated and properly presented to the abrasive-wheel, it 1s necessary that they should be turned in the raceway, and this is accomplished by forcing the driving-ring 23 toward the raceway, so as to keep the balls in engagement with the raceway, and consequently in proper position to be acted upon by the abrasive-wheel. and also to hold them in such contact with the. raceway that they will be rotated and avoid the formation of facets on the balls.

The springs may be adjusted to give the desired tension. As before stated, the action of the spring 481s equal against the sleeves 14 and 30, while the spring 9 only exerts a tension on the drive-ring.

My invention, through the spring 18, gives a constant pressure to the abrasive wheel, keeping itworking at its maximum capacity and, at the same time. giving a similar, or slightly greater, equalizing pressure against the drive-ring. By doing this. I overcome or counteract the tendency of the abrasive .wheel to press the balls away from the raceway when in action, permitting of a much I less pressure against the raceway at any period below the-maximum cutting capacity of-the abrasive wheel.

If found desirable, I can give an increasing pressure on the drive-ring, as increasing pressure is applied to the abrasive wheel by increasing the length of the lever 43.

This application of pressure on the drive- -ring and abrasive-disk simultaneously, as can readily be seen, permits of the minimum pressure needed to control the balls in their raceway, under any or all differences of operation.

I claim:

l. A ball-grinding machine, comprising a fixed raceway providing a slot through which the balls project, an adjustable abrasive disk and an adjustable drive-ring on opposite sides of said raceway, and an equalizing connection between said disk and said ring, whereby adjustment of one toward the other and the raceway will tend to cause a movement of the other toward it and the raceway.

2. A ball-grinding machine, comprising a fixed raceway providing a slot through which the balls project, an adjustable abrasive disk and an adjustable drive'ring on opposite sides of said raceway, and a yieldable equalizing connection between said disk and said rin whereby adjustment of one toward the ot er and the raceway will tend to cause a movement of the other toward it and the raceway.

3. A ball-grinding machine, comprising a fixed raceway providing a slot through which the balls project, an adjustable abrasire disk. and an adjustable drive-ring on opposite sides of said raceway, and a connection between said disk and said ring, whereby adjustment of one toward the'other and the raceway will tend to cause a movement of the other toward it and the raceway but producing a preponderating pressure upon the ring. Y

4. A ball-grinding machine, comprising-a raceway and an abrasivedisk, a drive-ring arranged in line with said raceway, eccentric to the said abrasive-disk, the mountings ineluding,- ext-cwally-threaded sleeves. nuts on said sleeves, yokes engagin with said nut-s, a two-part connecting-rod between the ends of the yokes, a spring tending to separate the parts of the connecting-rod and hence force the nuts toward each other, and a spring exerting an influence onthe drivering without affecting the tension on the abrasive-disk.

5. A ball-grinding machine, comprising a %l1I1Cl1Ilg-Ci1S- a raceway eccentric to the c riving-disk, a driveri-n concentric with the raceway, means for driving the abrasive- -disk and drive-ring, externally-threaded tubular bearings for the abrasive-disk and drive-ring, nuts on said bearings by which they ma be moved longitudinally, p1votallymounte yokes bearing against saidnuts, the ends of the yokes coupled by a twopart telescopic connecting rod, stops on each part of the connecting-rod, and a spring-between the said-stops and adapted to lengthen the connecting-rod, whereby the nuts are forced toward each other, an adjustable bearing on one member of the connectingrod,.and a spring between said bearing and the adjacent yoke, whereby pressure is applied to the drive-ring,independent of the pressure of the spring between the parts of the connecting-rod.

In testimony whereof, I have signed this specification.

\VALTER B. GARDINER. 

